In many single wafer or batch spray wafer processing systems, processing solutions (e.g., etching solutions or rinsing solutions) are used to treat a wafer during various processing steps. During processing, it is desirable that the wafer handling apparatus be capable of providing a high wafer throughput while maintaining careful and precise handling of each individual wafer. The wafer is often releasably gripped by its edges by edge grippers to secure the wafer and minimize contamination of the top and bottom wafer surfaces. However, a small amount of processing solution and residue can become trapped between the edge grippers and the edge of the wafer. This small amount of processing solution and other residue can be hard to remove during subsequent rinse steps and can wick out onto the wafer surface and can cause contamination in areas near the wafer edge contacted by the edge gripper.
Accordingly, new methods are required to address these contamination problems.